{"id":"PYSEC-2021-367","details":"The module `AccessControl` defines security policies for Python code used in restricted code within Zope applications. Restricted code is any code that resides in Zope's object database, such as the contents of `Script (Python)` objects. The policies defined in `AccessControl` severely restrict access to Python modules and only exempt a few that are deemed safe, such as Python's `string` module. However, full access to the `string` module also allows access to the class `Formatter`, which can be overridden and extended within `Script (Python)` in a way that provides access to other unsafe Python libraries. Those unsafe Python libraries can be used for remote code execution. By default, you need to have the admin-level Zope \"Manager\" role to add or edit `Script (Python)` objects through the web. Only sites that allow untrusted users to add/edit these scripts through the web - which would be a very unusual configuration to begin with - are at risk. The problem has been fixed in AccessControl 4.3 and 5.2. Only AccessControl versions 4 and 5 are vulnerable, and only on Python 3, not Python 2.7. As a workaround, a site administrator can restrict adding/editing `Script (Python)` objects through the web using the standard Zope user/role permission mechanisms. Untrusted users should not be assigned the Zope Manager role and adding/editing these scripts through the web should be restricted to trusted users only. This is the default configuration in Zope.","modified":"2023-03-14T07:01:09.428084Z","published":"2021-07-30T22:15:00Z","withdrawn":"2023-03-14T07:01:09.428084Z","references":[{"type":"WEB","url":"https://github.com/zopefoundation/AccessControl/blob/master/CHANGES.rst#51-2021-07-30"},{"type":"FIX","url":"https://github.com/zopefoundation/AccessControl/commit/b42dd4badf803bb9fb71ac34cd9cb0c249262f2c"},{"type":"ADVISORY","url":"https://github.com/zopefoundation/AccessControl/security/advisories/GHSA-qcx9-j53g-ccgf"}],"affected":[{"package":{"name":"zope","ecosystem":"PyPI","purl":"pkg:pypi/zope"},"ranges":[{"type":"GIT","repo":"https://github.com/zopefoundation/AccessControl","events":[{"introduced":"0"},{"fixed":"b42dd4badf803bb9fb71ac34cd9cb0c249262f2c"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.0"},{"fixed":"4.3"},{"introduced":"5.0"},{"fixed":"5.2"}]}],"versions":["4.0","4.1","4.1.1","4.1.2","4.1.3","4.2","4.2.1","5.0","5.1","5.1.1","5.1.2"],"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/zope/PYSEC-2021-367.yaml"}}],"schema_version":"1.7.3"}